Endometrial Cancer Flashcards
What is endometrial cancer?
What are most cases?
- cancer of the endometrium (lining of the uterus)
- 80% cases are adenocarcinoma
- it is an oestrogen-dependent cancer
oestrogen stimulates the growth of endometrial cancer cells
When should endometrial cancer be presumed?
- any women presenting with postmenopausal bleeding has endometrial cancer until proven otherwise
- diabetes + obesity are key risk factors
- 90% cases are in women > 50
- 4th most common cancer in women
- > 75% 5-year survival
What is endometrial hyperplasia?
- a precancerous condition in which there is thickening of the endometrium
- most cases return to normal, but 5% become endometrial cancer
What are the 2 types of endometrial hyperplasia?
endometrial hyperplasia without atypia:
- the cells appear normal-looking and are unlikely to become cancerous
atypical hyperplasia:
- there is an increased risk of cancer as cells appear abnormal
How is endometrial hyperplasia treated?
- it is treated with progestogens
- the intrauterine system (e.g. Mirena coil) can be used
OR
- continuous oral progestogens such as levonorgestrel
What are the risk factors for endometrial cancer related to?
- the risk is associated with the amount of unopposed oestrogen the endometrium is exposed to
- unopposed oestrogen is oestrogen without progesterone
- unopposed oestrogen stimulates the endometrial cells and increases the risk of endometrial hyperplasia + cancer
What risk factors are associated with an increased exposure to unopposed oestrogen?
- increased age
- earlier onset of menstruation
- late menopause
- obesity
- no / few pregnancies
- oestrogen only HRT
- tamoxifen
- polycystic ovarian syndrome
- obesity is a RF as oestrogen within the fat stimulates the endometrium
- smoking slightly reduces the risk
What are the 4 different types of endometrial cancer?
- adenocarcinoma (endometrioid type) - 90%
- serous papillary carcinoma (5%)
- clear cell carcinoma (4%)
- sarcomas
Why is PCOS a risk factor for endometrial cancer?
- there is increased exposure to unopposed oestrogen due to a lack of ovulation
- ovulation results in the production of a corpus luteum
- the corpus luteum produces progesterone during the luteal phase
- without ovulation and a CL, there is no production of progesterone and the endometrium is exposed to unopposed oestrogen
How is the endometrium protected against unopposed oestrogen in PCOS?
- women should have one of:
- intrauterine system (e.g. Mirena coil)
- combined contraceptive pill
- cyclical progestogens to induce a withdrawal bleed
Why is obesity a risk factor for endometrial cancer?
- adipose tissue is the primary source of oestrogen in postmenopausal women
- adipose tissue contains aromatase
- aromatase converts androgens into oestrogen
- more adipose tissue = more androgens converted into oestrogen
- the oestrogen is unopposed after the menopause in women who are not ovulating
- this is because there is no corpus luteum to produce progesterone
What are the risk factors for endometrial cancer not related to oestrogen exposure?
- type 2 diabetes
- hereditary nonpolyposis colorectal cancer (HNPCC) or Lynch syndrome
Why is T2DM a risk factor for endometrial cancer?
- there is increased production of insulin
- insulin stimulates the endometrial cells and increases the risk of endometrial hyperplasia + cancer
What are the protective factors for endometrial cancer?
- combined oral contraceptive pill
- Mirena coil
- increased pregnancies
- cigarette smoking
What is the main presenting symptom of endometrial cancer?
!! postmenopausal bleeding !!
- this is bleeding occurring at least 1 year after cessation of periods
- 10% of women with PMB will have malignancy
How is transvaginal US used to exclude endometrial cancer?
- it assesses endometrial thickness
- normal thickness after the menopause is < 4mm
- if thickness is > 4mm, further investigations are performed
- this is harder to perform on premenopausal women as the endometrium may be thickened if they are about to have a period
- biopsy is usually performed for certainty
What is involved in a pipelle biopsy?
- a thin tube (pipelle) is inserted through the cervix into the uterus with a speculum examination
- the tube fills with a sample of endometrial tissue
- this can be examined for signs of endometrial hyperplasia / cancer
How is endometrial cancer staged?
FIGO staging:
stage I:
- confined to the uterus
stage 2:
- involves the cervix
stage 3:
- spreads outside of the uterus to the lymph nodes, vagina, fallopian tubes or ovaries
stage 4:
- involves the bladder / rectum or distant spread beyond the pelvis
What is the treatment for stage 1 or 2 endometrial cancer?
total abdominal hysterectomy with bilateral salpingo-oophorectomy
- known as TAH and BSO
- removal of the uterus, cervix + adnexa
